Nature “Ocean Giants: Deep Thinkers” at 7 pm
In some respects, the brains of whales and dolphins are more complex than ours. Whales and dolphins work cooperatively, show empathy and are self-aware. “Deep Thinkers” finds out how clever – and how much like us – whales and dolphins might be.

Nova “Hunting The Elements” at 8 pm
What are things made of? It’s a simple question with an astonishing answer. Fewer than 100 naturally occurring elements form the ingredients of everything in our world — from solid rocks to ethereal gases, from scorching acids to the living cells in our body. David Pogue, lively host of NOVA’s popular “Making Stuff” series and personal technology correspondent for “The New York Times,” spins viewers through the world of weird, extreme chemistry on a quest to unlock the secrets of the elements. Why are some elements, like platinum and gold, relatively inert while others, like phosphorus and potassium, are violently explosive? Why are some vital to every breath we take while others are potentially lethal? Punctuated by surprising and often alarming experiments, Pogue takes NOVA on a roller coaster ride through nature’s hidden lab and the compelling stories of discovery that revealed its secrets.